A worrying noise from a K5

When I picked up my K5 (by the handgrip in my right hand) it was lifted in an upwards and to the right arc before being stopped in the normal position to take a picture.
As it stopped, there was a sliding sound from inside it, as if something heavy moved maybe 2mm to the right before its limit of movement stopped it. I let the left side of the camera drop and whatever it is slid back again!
It isn't the battery. I took it out and repeated the movements with the same result. I took the lens off and watched inside. everything visible remained firm. It is something quite heavy and dense inside the body. It is still under guarantee.
Suggestions?

It's the sensor assembly sliding around in it's anti shake housing. When powered up for taking pics it's in held place by it's electromagnets, which also serve to move it to compensate for camera shake ( and as an anti alias simulator in the K-3 ).

Perfectly normal This cut away shows what's sliding about

http://images.gizmag.com/inline/pentax-k-3-21.jpg

Smeggypants has probably hit the nail on the head there.
All being well that is all that you hear.

+1 Smeggy.

In fact, it's clearly referenced on Page 17 of the user manual.....but no-one reads those, of course!

Cheers.
Philip

That's a relief then! .............. Thank you all ..... and Philip, I shall take the fat white book to bed with me very shortly. You are quite right about the introductory bits getting skipped!

Time Pentax had a wee message on the back screen like 'no card in camera'
saying 'the clunk is normal'

Talking of noises, somebody likes my kind of music I see - Does it sound as good upside down?

Indubidably
must be the Perpetual Change that does it